Amnesty International has called on European nations to admit their involvement in operations of the US Central Intelligence Agency (CIA) that included torture of inmates.

The UK-based group’s counter-terrorism and human rights expert Julia Hall said on Tuesday that the governments could no longer "rely on unsubstantiated 'national security' grounds and claims of state secrecy to hide the truth about their roles in the torture and disappearance of people.”

She also urged justice for all the detainees who have suffered the ghastly practices such as waterboarding, sexual assault, as well as mock executions.

The call came following the release of a report by the US Senate that painted a gruesome picture of how the CIA tormented those suspected of committing acts of terror. The damning report also shed light on British spy agencies’ role in the inhumane practices as London is Washington's closest partner in the so-called "War on Terror.”

The Senate report made it crystal clear that foreign governments "were essential to the 'success' of the CIA operations,” Hall further said.

No European countries have been explicitly named in the US report. However, Amnesty says based on its research, Poland, Romania, and Lithuania allowed the CIA to run secret detention sites on their soil while British agents were involved in torture.The results of a parliamentary probe into allegations of British cooperation with Washington in torture will be published at end of 2015. Nevertheless, the rights group believes the investigation is "not independent.”

The controversial report was released by the Senate Intelligence Committee in late 2014 and presented a drastically redacted summary of the voluminous report on the CIA’s torture program during the administration of former President George W. Bush.